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A Quick Note on Image Compression
*Types of image compression are categorized as ‘lossy’ and ‘lossless’ *Lossless compression allows the user to reconstruct the original image upon decompression *Lossy compression, as the name implies, will loose some of the original images data
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•Types of image compression are categorized as lossy and lossless.
•Lossless compression allows the user to reconstruct the entire original image upon decompression, thus it does not interfere with a stego-image’s integrity.
•Lossy compression however will loose some of the original image’s data, therefore it will interfere with your communication when uncompressed.
•Some examples of formats using lossless compression are GIF and BMP.  An example of a lossy compression format is JPEG.
•If you were to convert your stego-image from a GIF to a JPEG and back it will more than likely compromise the integrity of your stego-medium.